Just Do It: Schema for Emails & the Review Action
Chances are excellent that a majority of your existing customers/users have a Gmail/Inbox email address.
Google provides arguably one of the most powerful messaging solutions available on the Web today and email marketers, whether they know it or not, can take full advantage.
One of the lesser-known aspects of the messaging platform is its support of semantic data.
By using Schema Markup within email it is possible to deliver some rather interesting functionality within the message body itself. Most Web professionals will likely be familiar with using schema markup on their website, but when you see what it can do within email, your mind is going to be blown!
Marketers can include rich markup that supports a variety of actions including event RSVP functionality, prompting users to submit a review or comment, as well as a variety of more generic actions for just about anything (including flight confirmations, et al). These "actions" essentially help marketers accelerate users' actions and/or highlight important information or tasks.
One of the most important/essential capabilities for any enterprise selling products or services, however, is the Review Action. When the code for the review action is included, Google "may" decide to show a review button next to the email and prompt the user for a numeric review value or a comment from the user (see image below).
Google graciously provides the necessary code snippets (in JSON-LD and Microdata) to get started with the Schema review action for emails so we won't go into the details here but a code sample is provided below that des illustrate the simplicity.
It's prudent, of course, to validate the embedded code within emails before actually hitting send. Fortunately, Google has also developed an Email Markup Tester to get the job done.
The Review Action Code (Microdata)...